Water Conservation by Calibration of Irrigation Systems

Introduction

Sixty to eighty percent of southern Nevada's water consumption is used for irrigation of yards and landscapes. Everyone can do his part to help conserve this precious resource.  Calibrating irrigation systems is an excellent way to save water with little or no sacrifice. There are many ways to conserve water in the landscape. First, plant more desert and drought tolerant plants adapted to southern Nevada. Second, a more efficient irrigation system that divides the shrubs and trees from turf areas in the watering schedules reduces consumption of water.  Third, using spray irrigation for turf areas and drip or low volume systems for shrubs and trees will also save water.  Knowing the landscape and being able to tell whether or not it needs water also helps to save.  Fourth, the amount of water needed in the middle of winter is going to be different than in June, July, and August, the hottest and driest months of the year. It is best to think of a time clock as an automated shut off system rather than just setting it and letting it run. If a landscape needs water, turn the irrigation system on (only on specified watering days). Fifth, in southern Nevada (except for an occasional monsoon rain) irrigating during the summer months is essential for plants to survive.  The time of day a person chooses to water is also important.  Early morning is best, as it is the coolest time of day, and it is also the time of day when there is little wind. 

Once established, many desert-adapted plants can survive with less water than most people think. This can be seen at homes where people have moved out and turned off the irrigation systems. Desert-adapted plants survive, while non-adapted plants die in a few days to a few weeks.  

In southern Nevada one cannot rely on the monsoons of the summer or occasional winter rain to carry the landscape plants through, except the very toughest natives. Even they will benefit with some supplemental irrigation. 

Familiarity with a yard and its water needs can also save water.  One, when lawns are dull, the leaf blades fold together, and footprints are left when walking on the lawn, it is time to water.  Two, check on shrubs and trees by probing the soil making sure it is moist several inches under the organic mulch. In the late afternoon of a hot day, if plants wilt or have very dull looking leaves, it is a good indication that they are dry and not getting enough water from the irrigation system. Three, never wait until plants are brown or in permanent wilt (will not come back after watering) to water. 

Whether in a severe drought or getting through a dry summer, knowing the amount of water a sprinkler system applies is an essential part of saving water in the landscape.  In southern Nevada most people irrigate only by time (minutes) rather than by the amount of water an irrigation system puts out. Although this idea of watering by minutes only has helped people save water in their landscape, more water can be saved by fine tuning the irrigation. Determine the amount of water put out at any given time, and then water less frequently to encourage deep root systems. It is also important to encourage the root system to expand as far from the trunk as possible.

For the complete document on how to calibrate your sprinkler system, use the link below to download the PDF version.